Fractions+B-1

**Fractions**
toc A definition of fraction is a numerical quantity that is not a whole number. Such as 1/2, or 1/5. 3/10.

__**Parts of a Fraction**__
The first thing to know about fractions is that it has a numerator and a denominator. The top part is the numerator and the bottom part is called the denominator 2.

__**Multiplying Fractions**__
Okay so now that you know all the parts to a fraction first lets learn how to multiply fractions In order to do that here's an example ** ||= ** Explanation ** || \frac{1}{2}*\frac{4}{7}=\frac{4}{14} math || So in order to do this all you have to do is multiply the numerators and denominators together. ||
 * = ** Example 1
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__**Dividing Fractions**__
Dividing fractions is easy! It's very very similar to multiplying except it has one extra step.

** ||= ** Explanation ** || \frac{1}{2}\div \frac{4}{7} =\frac{1}{2}* \frac{7}{4}=\frac{7}{8} math || ** Step 1 ** Flip the 2nd fraction.
 * = ** Example 2
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 * Step 2 ** Turn the division sign into a multiplication sign.
 * Step 3 ** Solve. ||

__**Adding Fractions**__
For Adding and subtracting fractions the first step you have to do is trying to find something called the least common denominator, also known as LCD.

To find the least common denominator, simply list the multiples of each denominator (multiply by 2, 3, 4, etc.) then look for the smallest number that appears in each list.

\frac{1}{5}+ \frac{1}{6} math || First we list the multiples of each denominator.
 * Example 3: ** Suppose we wanted to add 1/5 + 1/6. We would find the least common denominator as follows.
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Multiples of 5 are 10, 15, 20, 25, 30, 35, 40,... Multiples of 6 are 12, 18, 24, 30, 36, 42, 48,...

Now, when you look at the list of multiples, you can see that 30 is the smallest number that appears in each list

Therefore, the least common denominator of 1/5, 1/6 is 30. || \frac{1*6}{5*6}+ \frac{1*5}{6*5} math math =\frac{6}{30}+ \frac{5}{30} math || Now that we found the LCD there's also another rule that follows up, which is what you do to the bottom you do to the top. For the first fraction 1/5 and the common denominator is 30 so that means you multiplied 5 by 6 times in order to get 30. So you also multiply 6 by the top number to. Giving you 6/30. The same procedure was done for 1/6. The LCD was 30, so you multiplied 6 by 5 in order to get 30. And you also multiply that by the top giving you 5/30. || \frac{6}{30}+ \frac{5}{30}=\frac{11}{30} math || All you have to do now is add the numerators together but just carry over the 30. Giving you 11/30 which is the answer. ||
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__**Subtracting Fractions**__
Subtracting fractions is almost the same as addition. \frac{1}{5} - \frac{1}{6}=\frac{6}{30}- \frac{5}{30}=\frac{1}{30} math || ** Step 1 ** Find the common denominator which was 30.
 * = ** Example 4 ** ||= ** Explanation ** ||
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 * Step 2 ** Subtract only the numerators again and just carry over the denominator which gives you 1/30. ||

__**Fractions with Variables**__
So basically this time I’m going to show you how to do fractions using variables. This makes things a little more trickier because instead of dealing with numbers were dealing with letters. Don’t let them confuse you though.

\frac{x+3}{x-1} - \frac{x}{x+1} math math =\frac{(x+3)(x+1)}{(x-1)(x+1)} - \frac{x(x-1)}{(x+1)(x-1)} math math =\frac{x^2+x+3x+3}{(x-1)(x+1)}-\frac{x^2-x}{(x-1)(x+1)} math math =\frac{x^2+4x+3}{(x-1)(x+1)}-\frac{x^2-x}{(x-1)(x+1)} math math =\frac{5x+3}{(x-1)(x+1)} math math =\frac{5x+3}{x^2-1} math || ** Step 1 ** Find the common denominator which is (x+1)(x-1). ||
 * = ** Example 5 ** ||||= ** Explanation ** ||
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 * Step 2 ** Simplify the numerators using the distributive property, FOIL method, and by combining like terms.
 * Step 3 ** Subtract only the numerators again and just carry over the denominator.
 * Step 4 ** Simplify the common denominator.

Powerpoint about Fractions
Here's powerpoint which provides another format for learning about fractions. media type="custom" key="754877"

Further Discussion

 * What's the value of using least common denominator?